Automatic refrigerating apparatus.



No. 684,894. Patented Oct. 22, I90l.

S. C. WULCUTT.

AUTOMATIC BEFBIGERATING APPARATUS.

(Application filed Feb. 11, 1901.

(No Model.)

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UNITE STATES PATENT GEEICE.

AUTOMATIC REFRIGERATING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 684,894, dated October22, 190 1. Application filed February 11, 1901- Serial No. 46,769. (Nomodel.)

T0 on whom it may concern.-

Be it known that I, STEPHEN C. WOLCOTT, a citizen of the United States,and a resident of Brookline, in the county of Norfolk and State ofMassachusetts,have invented certain new and useful Improvements inAutomatic Refrigerating Apparatus, of which the following is aspecification.

My invention relates to an electrically-operated apparatus forperforming the functions of the apparatus disclosed in my priorapplication, Serial No. 40,746, filed in the United States Patent OfficeDecember 22, 1900.

Although the functions to be performed by this apparatus aresubstantially the same in nearly every particular as those performed bythe apparatus disclosed in my prior invention, yet I have found that anelectrical means for performing these functions is more desirable undercertain conditions than the compressed-air method disclosed in saidapplication.

For an understanding of my invention reference is made to theaccompanying drawing, in which a diagrammatical view of the entireapparatus is shown.

The compressor 1 is operated by an electric motor M in any well-knownmanner, and the source of the electric current is indicated by thedynamo D, which may be acentral powerstation. The water from thewater-main for cooling the refrigerant as it is compressed is suppliedthrough the pipe 2.

Numerals 3, 4, and 5 indicate 'a series of refrigerating-chambers, eachof which is provided with an expansion-coil. 6, 7, and 8, respectively.The inflow ends of these coils are connected to the maindistributing-pipe 9, which leads from the condenser, and the exhaustends thereof are all connected to a return-pipe 10, which conducts therefrigerant back to the compressor, so that said coils may be said to beconnected in parallel. Each refrigerating-chamber is provided with athermostat 12, 13, and 14, respectively. Each of these thermostats maybe of any wellknown form and preferably consists of two curved strips ofdifferent metals, which are riveted together and carry an arm at theirfree end, which will be swung back and forth, according to thevariations of the temperature to whichthe thermostat is subjected. Thethermostat 12 is provided with a single contact-point 15, which isconnected by means of a wire to one end of the coil of the solenoid 16.The opposite end of the solenoid-coil leads to one pole of thebattery B.The swinging arm of the thermostat 12 is connected by means of wire 29with the other pole of the battery 13. The bar 17 of the solenoid 16' isprovided with a cross-piece 18, which isadapted to engage and makeelectrical connection between the two contact-points 19 and 20,

when the solenoid is energized. A fixed bar 21 is arranged above thecross-bar 18, and a spring 22 around said bar 17 is adapted to to engagea shoulder on the upper endthereof and lift said bar 18 out ofengagement with the contact-points. when the solenoid is not energized.The contact-point 19 is connected by a main wire 23 to one pole of thedynamo, and the contact-point 20 is connected by the wire 24 to one poleof the motor. The opposite pole of the motor is connected to the dynamoby wire 240. An automatic rheostat R is interposed in the wire 24, sothat when the circuit is completed by means of the bar 18 the currentwill be gradually turned onto the motor M.

The operation of the thermostat 12 in controlling the temperature inchamber 3 is as follows: When the temperature in the chamber 3 is raisedabove the desired point, the bar of the thermostat'will be swung intoongagement with the contact-point 15, so that the circuit through the"solenoid 16 will be completed. The solenoid will draw the crossbar 18down into engagement with the contact-points 19 and 20, thus completingthe motor-circuit and starting the motor. The motor will continue inoperation until the temperature in the chamber 3 is again reduced to thedesired point. Then the arm of the thermostat will be swung away fromthe contact-point 15, breaking the circuit through the solenoid 16. andpermitting the spring 22 to draw the bar 18 out of engagement with thecontact-points, thus breaking the motorcircuit and causing the motor tostop. This only desirable when it is wished to keep the temperature ofthe chamber at almost exactly one point; but usually it is immaterial ifthe temperature varies as much as five degrees. If the temperature isreduced' one point below the average normal temperature and the motor isthen stopped and permitted method of regulation of a single chamber is'to remain at rest until the temperature is again raised in the chamberto a point somewhat above the desired normal temperature, the apparatusmay be operated more economically, as it will not be continuallystarting and stopping. To permit the temperature to vary withoutstopping and starting the motor, I employ the method of regulation shownin connection with chambers 4 and 5. In these chambers the thermostatsare provided with two contact-points at each side of the swinging arm,the contact-points in the chamber 4 being indicated by the numbers and26 and in chamber 5 by the numbers 27 and 28. The swinging arm of eachof the thermostats 13' and 14 is connected to the main wire 29, whichleads from the battery 13. The contact-points 25 and 27 are connected,respectively, to one end of the coil of solenoids and 31, and thecontact-points 26 and 28 are connected to the coils of solenoids 32 and33, respectively. The solenoids 30 and 32 are oppositely wound andarranged, and the opposite ends of the bar 34 are located therein. Thecentral part of said bar is provided with a cross-bar 35, which isadapted to be brought into engagement with the contact-points 36 and 37when the solenoid 30 is energized and to be drawn away from saidcontact-points when the solenoid 32 is energized. The solenoids 31 and33 are also arranged in precisely the same manner as the solenoids 30and 32 and are also provided with a common bar 38, which carries acrossbar 39, said bar being adapted to make an electrical connectionbetween the contactpoints 40 and 41. The contact-points 36 and 40 areboth connected to the main wire 23 from the dynamo, and thecontact-points 37 and 41 are both connected to the wire 24.

When the temperature in either of the chambers 4 or 5 is raised abovethe point desired, the arm of the thermostats 13 or 14 will swing intoengagement with their respective contact-points 25 or 27 and energizetheir respective solenoids 30 or 31, drawing the crossbars 35 or 39 downinto engagement with the contact-points 36 and 37 or and 41,respectively, completing the circuit to the dynamo and starting themotor. This part of the operation is precisely the same as previouslyexplained with respect to chamber 3. When the temperature in either ofsaid chambers 4 and 5 is brought down to the particular point desiredtherein, its thermostat will swing into engagement with itscontact-point 26 or 28, energizing its solenoid 32 or 33 and drawing thecontact-bars 35 or 39 out of engagement with their respectivecontact-points, thus breaking the circuit to the motor which wascompleted through these-bars.

It will be obvious that the thermostat in each chamber will be setaccording to the particular temperature desired in that chamber, sothat, for example, chamber 3 may be kept at approximately 20, chamber 4at 30, and chamber 5 at 40. Each of these thermostats operateindependently of the others,and when the temperature in one of saidchambers is brought down to the point desired it will simply break oneof the circuits from the dynamo to the motor, but the motor willcontinue in operation until all the chambers have been reduced to theirdesired points. When the temperature in the last chamber is brought toits particular point desired, the last circuit between the dynamo andthe motor will be broken and the motor will stop. If the temperature inany one of these chambers is raised above the point desired therein,theparticular solenoid which is connected to the thermostat in this chamberwill be energized, and the circuit will be completed from the dynamo andto the motor, starting the latter.

Instead of employing the battery B connections may be made with thedynamo-circuit, as indicated by the dotted lines a a, a resistance, suchas a lamp, being placed therein.

As the several coils in the several chambers are each connected to thesame compressor, it will be obvious that if some means were not providedfor disconnecting each particular coil from the compressor after thetemperature in the chamber in which the coil is located has been reducedto the point desired the compressor would continue to lower thetemperature in said chamber irrespective of the fact that its thermostathas acted to break one of the circuits between the motor and the dynamo.I therefore provide the inflow end of each coil with automaticback-pressure Valves 42, 43, and 44, respectively, said valves beingadapted to close their respective pipes when the pressure in theirrespective coils is raised above a certain point. Valves of thischaracter are well known in the art and need no specific description. Ialso provide the discharge end of each coil with adiaphragmvalve 45, 46,and 47, each of which is adapted to close its respective pipe whenpressure is applied to its diaphragm. These valves are also well knownin the art and need no further description. I connect thediaphragm-chamber of each of said valves 45, 46, and 47 to thewater-supply main 2 by means of the pipe 48 and suitable branch pipeswhich are connected to said pipe 48, and I provide a three-way valve 49,50, and 51, respectively, in each branch pipe and connect waste-pipes52, 53, and 54 to each valve, respectively. The handle of each valve isconnected to the bar of the solenoids 55, 56, and 57, respectively, sothat when either of these solenoids is energized the handle of the valvewhich is connected thereto will be moved in one direction. I alsoprovide springs 58, 59, and 60, which act to throw the respectivehandles in the opposite direction when their particular solenoid is notenergized. The coils of solenoids 55, 56, and 57 are respectivelyshunted onto the several circuits, which are completed by means ofcrossbars 18, 35, and 39, so that when any one of these circuits iscompleted by means of the said cross-bars its particular solenoid willbe en- EEO ergized, throwing the three-way valve, which is connectedthereto, to such a position that the diaphragm-chamber of'thediaphragmvalve which it controls will be open to the exhaust-pipe of thethree-way valve. When any one of these circuits is broken by itscross-bar, the spring which is connected to the opposite end of thehandle of the threeway valve for that circuit will throw said valve tothe opposite position, so that the pressure from the water-main will beopened to the chamber of the diaphragm-valve,which is controlled by saidthree-way valve, closing the exhaust end of its coil. When either of thevalves 45, 46, or 47 is closed by the water-pressure in the manner justdescribed closing the exhaust end of a coil, the pressure in the coilwill immediately begin to'increase, so that the back pressure thereinwill soon become suflicient to close the back-pressure valve at theinlet side of the coil. It will thus be seen that when the temperaturein any one of the chambers is brought down to the point desired the coilin that chamber is disconnected from the circulating system. When thetemperature in any one of these chambers is raised above the normal, thethermostat therein will move, so that one of the circuits to the motoris closed, the solenoid, which is shunted on this circuit, will becomeenergized, moving the three-way valve, which is connected thereto, sothat its connected diaphragm-valve will be opened. The pressure in thecoil will then be reduced, so that the back-pressure valve will open.

As set forth in my application above referred to, it is desirable toprovide means for automatically stopping the motor when the water-supplyfails or is turned off and to also shut off the water-supplyautomatically when the motor is stopped and turn the same on when themotor is started.

To accomplish the first function, above referred to, I employ a similarapparatus to that disclosed in my said prior application,

, which consists, essentially, of a diaphragmchamber 61, which isconnected to the watersupply pipe 2 above the point where the latterenters the compressor. The diaphragm of chamber 61 has a stem 62connected to the outer side thereof, and said stem is connected to aswitch 63, through which the return-current from the dynamo to the motorpasses. A spring 64 is provided on the outside of the diaphragm, so thatwhen the water runs. out of the chamber 61 into the compressor after thewater is shut off the spring 64 will move the diaphragm inwardly andopen the switch 63, breaking the circuit and stopping the motor.

In order to shut off the water-supply automatically when the motor isstopped for any reason, as by reason of its being stopped by theautomatic apparatus which is controlled by the thermostats in therefrigerating-chambers, I provide anautomatic valve 65 in thewater-supply main 2 between the chamber 61 and the compressor. Thisvalve may be of any well-known form which maybe automatically operatedby a current of.electricity. The form indicated in the drawing consistsof a valve the stem of which is connected to the piston in a cylinder66. An ordinary three-way slide-valve may be provided at one side ofsaid cylinder 66, so that when said slide-valve is in one positionwater-pressure from the water -main may be introduced through the pipe67, so as to open the valve 65, and when the slide-valve is in theopposite position the valve 65 may be closed by water-pressureintroduced through the same pipe, the discharge from the opposite sideof the piston in the cylinder 66 being provided for through thewaste-pipe 68. The construction referred to will be understood to be thesame as a simple form of slide-valve engine.

The stem 69 of the slide-valve is connected that when the current flowsthrough the wire 240 the solenoid will be energized, moving the stem 69of the pilot or slide valve, so as tocause the valve 65 to open. Whenthe current is shut off from the motor, so that there is no longer aflow of electricity through the wire 240, the solenoid will no longer beenergized and the pilot-valve will be moved to the opposite position bymeans of a spring 71, causing the valve 65 to close.

It will be obvious that this system for controlling the temperature in aseries of refrigerating-chambers, as well as the system shown in myprior application, may be applied to the circulating-brine system ofrefrigeration, as well as the expansion system herein referred tothatis, the motor instead of operating a compressor will operate abrine-pump, which will cause the brine to circulate through the variouscoils in the same manner that the compressed gas is described ascirculating above. As the coils will be connected in parallel, as shownin thedrawing, the circulation through any one of thecoils may bestopped without interfering with the circulation through the othercoils, and when the circulation through the last coil is closed themotor will stop simultaneously.

In the brine system the automatic backpressure valves at the inlet endof the coils would be omitted, as would the automatic devices used inconnection with the water-sup ply pipe to the compressing apparatus.

The particular electrical appliances described are simply illustrative,and other electrical appliances which perform the same functions may besubstituted.

I furthermore consider it within the scope of my invention to substitutea hydraulic or steam motor for the electric motor shown herein,providing an independent supply-pipe to the motor for each chamber, andproviding an automatic valve in each supply-pipe,which 7 is controlledby its respective thermostat, so that it may be opened fully and closedpartially or fully, according to therequirements of the particularchamber inwhich the thermostat is located.

Having described my invention, what I' tions in temperature in thechamber in which a particular thermostat is located.

2. The combination in a refrigerating apparatus of a series ofrefrigeratingecoils which are connected in parallel, an electricmotorfor causing a circulation of the refrigerating medium through each ofsaid coils, a refrigerating-chamber for each coil, a thermostatineachchamber, anindependent circuit for each chamber between thegenerator and motor, electrically-operated means for controlling theflow of electrical current througheach circuit and electricalconnections between each of said thermostats and its correspondingcircuit-controller, whereby each circuit may be automatically controlledaccording to the variations of temperature in each chamber.

3. The combination of a refrigerating apparatus ofa series ofcirculating-coils which are connected in parallel, an electric motor forcausing a circulation of the refrigerating medium through each coil, achamber for each coil, a thermostat for each chamber, and in dependentcircuit for each thermostat between the source of the electrical supplyand the motor, means controlled by each thermostat for controllingtheflow of the current through its respective circuit according to thevariations in temperature in its particular chamber, an automatic valvein each coil, electrically-controlled means for opening and closing saidvalves, electrical connections between each of said valve-controllingmeans and its corresponding independent motor-circuit, whereby eachvalvemay be automatic ally controlled according to the flow of electricitythrough its corresponding motor-circuit.

4. An automatic refrigerating apparatus comprising a compressor, anelectric motor for driving the same, an OXPfiMSlOH-COHCOH- nected tosaid compressor, a water-supply pipe for said compressor, an automaticvalve in said pipe, and electrical controlling means for said valvewhich are connected to the circuit between the motor and generator, saidmeans being adapted to close said valve when said circuit is broken andto open said valve when said circuitis closed.

5. A system which is adapted to maintain different temperatures in aseries of chambers comprising a series of circulating-coils which areconn ected'in parallel, a chamber in which each coil is located, a motorfor causing the circulation through each coil, an independent conductorfor each coil between the source of powerand said motor, a thermostat ineach chamber, and means for controlling communication between the sourceof power andthe motor through each conductor, the means for controllingcommunication through each conductor being controlled by itscorresponding thermostat accordingto the variation of temperature in thechamberin which a particular therm ostat is located.

6. A refrigerating apparatus comprising a.

is located, a motor for causinga circulation" througheach coil,anindependent conductor for each coil between the source of power andsaid motor, a thermostat in each chamber, means for controllingcommunication. be

tween the source of power and the motor:

through each conductor, the means forcontrolling comm u nication througheachconductor being controlled by its corresponding thermostat accordingto the variations of'temperature in the chamber in which a particularthermostat is located, an automatic valve in each coil, connectionsbetween each con"- ductor and its corresponding valve, and means forcontrolling each valve, said means beingcontrolled by the motivepower'asit' passes through the several conductors.

7. The combination in a refrigerating apparatus of a series ofrefrigerating-"coils which are connected in parallel, an electric 'motorfor causing a circulation of the refrigerating medium through each ofsaid coils, a refrigerating-chamber for each coil, a thermostat ineachchamber, an independent circuit for each chamber between thegenerator and motor, an automatic switch in each circuit, connectionsbetween each switch and its correspondingthermostat', and meansforcausing" each thermostat to open its corresponding switch when thetemperature'in itschamber' falls to a predetermined point, and to closethe same when the temperature therein is raised above a predeterminedpoint, whereby the motor will be stopped when the temperature in eachchamber is brought to the particular point desired therein, and will.be. started when the temperature in any one of said chambers is raisedabove the point desired therein.

In testimony whereof I have affixed my signature in presence of twowitnesses.

STEPHEN C. WOLCOTT. Witnesses:

LOUIS I-I. HARRIMAN, Gno. E. UoKnR;

